Aqueous developable deep UV negative resist containing benzannelated acetic acid and novolak resin

Abstract

A radiation-sensitive mixture useful as a negative-working photoresist composition comprising: (a) at least one novolak resin; and (b) a photoactive benzannelated acetic acid selected from formula (I): ##STR1## wherein X is either an oxygen, sulfur or ##STR2##

WHAT IS CLAIMED IS: 
     
       1. A radiation-sensitive mixture useful as a negative-working photoresist composition comprising the admixture: (a) at least one novolak resin; and   (b) a photoactive benzannelated acetic acid selected from formula (I): ##STR6##   wherein X is either an oxygen, sulfur or ##STR7##   
     
     
       2. The radiation-sensitive mixture of claim 1 wherein said novolak resin is selected from the group consisting of phenol-formaldehyde novolak resins and cresol-formaldehyde resins. 
     
     
       3. The radiation-sensitive mixture of claim 1 wherein (a) is from about 70 to about 99 percent and (b) is from about 30 to about 1 percent of the non-volatile content of said mixture. 
     
     
       4. The radiation-sensitive mixture of claim 1 wherein said benzannelated acetic acid is xanthene-9-carboxylic acid. 
     
     
       5. The radiation-sensitive mixture of claim 1 further comprising one or more additives selected from the group consisting of solvents, actinic and contrast dyes, anti-striation agents, plasticizers and speed enhancers.